Struts is a framework for fast development of J2EE Web applications based on MVC Architechture. It has three components - Model, View and Controller. It clearly seperates business logic and designing aspects of a web project. Each developer can use his seperate JSP's and Action/ActionForm's in his own sandbox, thus eliminating the problem of work division for a Project Leader. Reading from a book would give you better understanding. Further reading suggested at:

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